Conjugated caged olefins, such as C.sub.60 and analogous molecules thereof, have been found to be extraordinarily susceptible to the attack of a variety of chemical reagents. Particularly, they all exhibit high reactivity toward multiple additions of organic free radicals. This reactivity is, presumably, correlated to the intrinsically large electronegativity of such molecules.
Several functionalized fullerene derivatives have been reported for the biochemical or medical related studies. For example, bis(phenethylamino-succinate) C.sub.60 inhibited the HIV-1 protease. Friedman, et al., J. Am. Chem. Soc. 1993, 115, 6506. As another example, photoactivated water-compatible monofunctionalized C.sub.60 showed DNA-cleaving activity and in vitro cytotoxicity against the HeLa S3 cell line. Tokuyama, et al., J. Am. Chem. Soc. 1993, 115, 7918. Both activities were eliminated in the absence of a light source.